Which files are required for a Docker container action in addition to the source code?

Dockerfile: The Dockerfile is required for Docker container actions. It defines the environment for the action, specifying the base image, dependencies, and any commands to set up the action’s runtime inside the container.

action.yml: The action.yml file is required for all GitHub Actions, including Docker container actions. It contains metadata about the action, including the inputs, outputs, and the runtime environment (which in this case is Docker, defined under runs.using).